If you have "Grand Theft Auto IV" renamed for example "Grand Theft Auto MODDED" Spark IV will not find it.

Any one of these issues has caused me that same error. Happy Hunting.

As far as derby cars go, i would say you could use the old clunker the Vigero 2. It has a missing fender and a popping exhaust. You can make the body fold up a little more by going into the common / data / handling file and changing the deformation damage and the engine damage values.
Scroll down the left side of the list until you see the Vigero 2. Move to the right until you get under the columns that have
Dc Dw Dd De . Change Dd (Deformation Damage) to a higher number, like 1.2 (the higher the number the easier the body takes damage, but you have to restart the game each time you change it). Then change the De (Engine Damage) to a lower number, say 0.6, so it lasts longer without blowing up. Now the car's engine will last a long time and take beating even though it may be hard to drive so smashed up. Enjoy

Alright, i think i found out the problem(something simple...of course). I'm using game version 1.0.7, even though I could have swore i was using 1.06. I must have patched somewhere down the line, and not have realized it.

Is there any way to patch back easily so i can download the cars, or do i have to uninstall and repatch from 1-6? I'm assuming sparkIV doesn't have a 1.0.7 version. Also, my scripthook file looks as follows: